1. Field of the Invention
The present invention relates generally to the field of concrete form systems. More specifically, the present invention discloses a support apparatus including a tie lock tool and a clamp for use with concrete form panels.
2. Statement of the Problem
Concrete form systems have been used for many years for concrete wall construction. In these systems, form panels are arranged opposing one another to provide a space into which concrete is poured to form the wall. Form ties, extending between and secured to the form panels, maintain a fixed distance between the form panels. After the form system is erected, concrete is poured between the form panels and allowed to harden, after which the form panels are removed.
The form ties are often secured to the form panels using a tie lock tool. Conventional tie lock tools, such as that. disclosed in co-owned U.S. Pat. No. 4,304,388, have a lock member with a single claw that grasps a head of the form tie. Aligning the head of the form tie to fit onto the single claw of the conventional tie lock tool can be labor intensive. For instance, at one time the head is too low to catch on the single claw, and another time the head is too high to catch on the single claw. Therefore, a worker must align the head with the claw while rotating the lock member to the locked position. Often, this process requires the assistance of a second worker. Therefore, a need exists to provide a tie lock tool that aligns the head with the claw.
In addition, a single claw can only grasp a loop head or a head having a hole formed therein. However, form ties having different head styles are available, such as button heads. U.S. Pat. No. 4,304,388 discloses a tie lock tool having two claws for grasping a button head, but the head must still be aligned to fit between the two claws. Therefore, a need also exists to provide a tie lock tool that can be used with form ties having different types of heads, for example, a button head or a loop head.
The lock member of the conventional tie lock tool is rotatably attached using a rivet. When concrete is poured between the form panels, substantial pressure is placed on the form ties, causing the claw of the tie lock tool to bear a substantial load. Therefore, a need exists to reduce this load on the claw.
Clamps are often used to secure a strong back (conventionally 2.times.4 lumber) to the form panels to support the concrete form system. Conventional clamps, such as that disclosed in co-owned U.S. Pat. No. 4,304,388, have a 3-gauge wire yoke that attaches to the tie lock tool. However, these clamps only provide a working load of 1,000 lbs.
In some circumstances, it is be desirable to increase the total load-bearing capacity above 1,000 lbs, for example, when longer or wider walls are poured in a concrete form system. Therefore, a need exists to provide a support apparatus that can handle such increased loads by increasing the strength of strong back clamps.
Conventional clamps are made to secure a conventional 2.times.4 lumber (11/2 inch wide.times.31/2 inch deep) strong back. However, 2.times.4 lumber is not always made to industry standards, and in some cases, 2.times.4 lumber sizes can vary from that of a conventional 2.times.4. Therefore, when the depth of the strong back is too small, the conventional clamp only loosely holds the strong back to the form panel. On the other hand, when the depth of the strong back is too large, the conventional clamp is difficult to close, especially if the lumber is hard (e.g., where there is a knot in the lumber). Likewise, different concrete jobs can require different size strong backs be used (e.g., 2.times.6 lumber). Thus, conventional clamps only work consistently with conventional size strong backs. A need therefore exists to provide a clamp that can be adjusted to secure strong backs of various depths.
In addition, a clamp must be functional under working conditions that include splattering concrete. Thus, a need exists to provide a clamp will not be easily obstructed. Furthermore, it is desirable to provide a clamp that can be attached by a single worker, possibly using a single hand. Therefore, needs exist to provide a clamp that will not fall out of position before the worker can connect it, and a clamp that will not slip with respect to the strong back as it is being tightened.
Finally, many concrete contractors already have a set of conventional tie lock tools and conventional clamps for use with concrete form systems, and only want to supplement their existing equipment or replace broken hardware. Therefore, yet another need exists to provide a tie lock tool and a clamp that can be used with conventional concrete form systems and existing hardware.
Support apparatuses for concrete form systems have been used in the past, including the following:
Inventor U.S. Pat. No. Issue Date Gates 3,908,956 Sep. 30, 1975 Gates 4,158,452 Jun. 19, 1979 Gates 4,304,388 Dec. 8, 1981 Gates 4,899,978 Feb. 13, 1990 Page 5,110,083 May 5, 1992
U.S. Pat. No. 3,908,956 relates to a free-standing upwardly-convergent pouring form that is held in place by tie members and anchor members. Opposite ends of the tie members are releasably connected to their respective panels with latches.
U.S. Pat. No. 4,158,452 teaches a clamping lock for use with a looped tie in a concrete form. An anchor lock having a tapered claw is mounted on the clamping lock so that its claw can enter into a tie loop to secure the tie to the clamping lock and to tension the tie.
U.S. Pat. No. 4,304,388 discloses a form tie lock tool having a lock member for use with hand-set concrete panels and an anchor lock member for use with gang form concrete panels. An alternative embodiment discloses using a form tie having a button head with a modified tie lock tool 104 having a double claw arrangement (e.g., FIGS. 10-13).
U.S. Pat. No. 4,899,978 discloses a form tie lock that is releasably locked in an open position and swings over center to a closed position.
U.S. Pat. No. 5,110,083 discloses a Ross Staging Bracket that holds sections of forming walling in parallel rows. A rotatable lock means for engaging with a form tie is pivotally mounted to and beneath a first horizontal waler support plate.
None of the above patents provide a solution to the above-stated needs.